Interval timer



Dec. 8, 1970 BOWMAN ETAL '3,546,557

I INTERVAL TIMER Filed May 9, 1967 4 sheetssneet 2 BY I m4/m 7W a f @www12/Wm D'ec. 8,11970 Filed May 9, 1967 J. BowMAN ETAI- INTERVAL TIMER 4 Sheets-Sheet 4 United States Patent O Ohio Filed May 9, 1967, Ser. No. 637,191 Int. Cl. H0211 3/00 U.S., Cl. S18-484 14 Claims ABSTRACT OF THE DISCLOSURE Interval timer having reset lever, setting a timer motor energizing cam, to eiect starting of a timer motor, and having an interval control cam energizing a circuit. The reset lever is manually actuated and rotates the timer motor energizing cam through a pawl and single toothed ratchet to start the timer motor after the completion of a timing cycle. Repeated actuation of the reset lever is ineffective to lengthen the cycle of energization of the timer motor, and is thereby ineiective to vary the time interval of energization of the circuit determined by the interval control cam. An interval modifying cam having clutching engagement with the interval control cam and adjustable by a knob independently of the timer motor cam is provided to vary the time interval.

BACKGROUND OF THE INVENTION The timer of the present invention is particularly adapted to energize the water ll valve of an ice maker, adapted for use in home refrigerators, and is manually set to energize the timer motor and initiate the interval of opening time of the water till valve. Heretofore, such timers have been manually reset to start the timer motor to rotate a timer motor cam regulating the on position of the timer motor, and to rotate at least one additional cam, to time energization of the solenoid of the water fill valve. In such timers, the reset device has been so arranged that many times it is needlessly operated after starting the timer motor, which prolongs the cycle of operation of the motor and may prolong or interrupt the cycle of operation of the water ill valve. This may result in over filling the ice mold trays or in operating the timer motor to move the water lill valve control cam beyond its start position with the result that the timer system frequently comes out of time to the extent that the interval of operation of the Water fill valve will be reduced t underfill the tray.

The timer of the present invention overcomes these deficiencies by so arranging the motor energizing cam and the reset device setting this cam to an initial motor energizing position, that operation of the reset device will have no eiect on operation of the timer motor after the timer motor has once been placed into operation, and until the timer motor has come to a complete stop.

SUMMARY OF INVENTION AND OBJECTS In carrying out the present invention we drive two timer cams from a constant speed timer motor, one of which timer cams is operable to initiate energization of the timer motor and maintain the motor in operation for a predetermined time interval, and the other of which timer cams is operable to close and maintain an energizing circuit closed for a preselected time interval. The time of energization of the energizing circuit may be modified by a modifying cam having clutching engagement with the circuit energizing cam, which is adjustable to vary the on time of the energizing circuit without affecting operation of the timer motor. We further provide a resetting mechanism for the motor control cam resetting the cam after the termination of operation of the timer motor, to again initiate energization of the motor, and so arrange the resetting mechanism that it is ineffective to vary the time of operation of the motor regardless of the number of times it is operated during a cycle of operation of the motor.

A principal object of the present invention, therefore, is to provide a novel and improved form of interval timer in which the time interval of energization of an energizing circuit is controlled by a timer cam positively driven by the timer motor and in which the length of time of energization of the circuit may be selected without alecting operation of the timer motor.

Another object of the invention is to provide an improved form of control means particularly adapted for controlling the cycle of operation of a ll valve for an ice maker and the like, in which the time of the iilling cycle may be selected in accordance with a preselected quantity of water required to be delivered by the water ill valve.

Another object of the invention is to provide a simple and improved form of interval timer, controlling the time of energization of an energizing circuit and having at least two timer cams, one of which controls the energization and on time of the timer motor, and the other of which controls the time of energization of the energizing circuit, in which the motor cam may be manually reset to initiate energization of the timer motor, and in which the resetting means has no affect on the time of operation of the timer motor once operation of the motor is initiated and during the entire preselected time of operation of the motor, regardless of the number of times the resetting means may be operated.

A further object of the invention is to provide an improved form of interval timer having a motor cam initiating and timing operation of the timer motor and having a second cam initiating the making of an energizing circuit, and controlling the on time of the circuit, with a modied cam having clutching engagement with the second cam to enable the length of the on time of the circuit to be preselected, in which adjustment of the modifying cam has no affect on the time interval of operation of the timer motor.

These and other objects of the invention will appear as the following specification proceeds and with reference to the accompanying drawings.

FIG. l is a plan View of a timer constructed in accordance with the principles of the present invention, with certain parts of the cover broken away in order to show certain of the timer switches.

FIG. 2 is a partial fragmentary view taken substantially along the aXis of rotation of the timer cams, with certain parts removed and with certain other parts broken away.

FIG. 3 is a side view of the timer shown in FIG. 1.

FIG. 4 is a fragmentary side view of the top part of the timer casing looking at the opposite side of the timer from FIG. 3.

FIG. 5 is a partial fragmentary sectional view taken through the timer cam shaft, showing the interval timer cam in end View and showing the modifying cam by broken lines; and

FIGS. 6, 7, 8 and 9 are transverse sectional views taken substantially along the timer shafts of modied forms of timers constructed in accordance with the principles of the present invention.

DESCRIPTION OF PREFERRED EMBODIMENT In FIGS. 1, 2 and 3 of the drawings, we have shown an interval timer including a casing 10 having parallel side walls 11 and 12, end walls 13, a bottom wall 14 and a top cover 15, generally L-shaped in form and extending along the top of the side wall 11 over the top of the casing 10 and downwardly along the outer end portion of the casing into abutting engagement with the top portion of the side wall 12.

The bottom wall 14 has an opening 16 therein extending between the side walls 11 and 12, through which a reset lever 17 extends. The reset lever serves to initiate energization of a timer motor 19 in a manner which will hereinafter more clearly appear as this specification proceeds.

The timer motor 19 is mounted on the outside of the side wall 12, and may be a conventional form of synchronous electric motor of a type commonly used to drive timer cams, at uniform rates of speed. The timer motor 19 has a gear reduction casing 20 secured thereto and forming a part thereof and containing reduction gearing (not shown) affording a one-way drive to a shaft 21 having a pinion 22 thereon. The pinion 22 extends within the timer casing into a drive socket 23 formed in an enlarged diameter end portion 24 of a timer shaft 25. Said timer shaft serves to rotatably drive spaced timer cams 26 and 27, mounted thereon.

A switch plate 29, made from an insulating material is disposed above the timer cams 26 and 27 and is suitably mounted in the timer casing to extend horizontally thereacross. The switch plate 29 has an open portion 31, in registry lwith the cams 26 and 27. A contact bar 30 extends across said open portion and may be riveted or otherwise secured to the underside of said switch plate. A terminal 31a extends along the top of the switch plate 29 and is connected with the contact bar 30, as by a rivet 32, riveting said Contact bar to the underside of said switch plate. The terminal 31a has an insulated conductor 33 connected thereto and leading therefrom along an insulating sleeve 35, extending outwardly of the side wall 11 of the timer casing. A ground conductor 36 also extends from the insulating sleeve 35 into the timer casing and has a terminal 37 on its end, riveted to the top of the switch plate 29 and to a terminal 39 as by a rivet 40. The terminal 39 has a ground conductor 41 connected thereto and leading therefrom and out through vthe side wall 11 of the timer casing 10 through and along an insulating sleeve 42.

The insulating sleeve 42 has energizing conductors 43 and 44 leading therefrom within the timer casing 10. The conductor 43 may serve as a positive conductor and has connection at its .free end with a terminal 45 extending along the top of a switch arm 46 and riveted thereto as by a rivet 47, which rivet also serves to rivet an end of the switch arm 46 to the top of the switch plate 29.

The conductor 44 may establish an energizing circuit to energize a device to be energized, such'as, the solenoid of a water fill valve for an ice maker, or any other device to be energized for a predetermined time interval. The conductor 44 has a terminal 48 on one end thereof, within the timer casing and riveted to the stationary end of a switch arm 49 as by a rivet 50. The switch arms 46 and 49, respectively, have contacts 51 and 53 thereon biased into engagement with the contact bar by the resiliency of said switch arms. Said switch arms may be made from a phosphor bronze or other form of spring material forming a good conductor for current, and have angularly downwardly turned outer follower end portions 55 and 56 respectively engageable with raised camming surfaces 57 and 58 of the respective cams 26 and 27 to move the contacts 51 and 53 out of engagement with the contact bar 30, as shown in FIG. 2.

The timer cam 26 is mounted on the timer shaft 25 for free relative movement with respect thereto, and is biased into engagement with a shouldered portion 61 of the shaft 25 as by a compression spring 63. Said compression spring is seated at one end on the inner face of the timer cam 27 and at its opposite end on a washer 69 abutting an inner end of a hub portion 70 of the timer cam 26. The timer cam 26 has a drive lug 71 formed integrally therewith spaced radially of the axis of rotation of said timer cam and extending axially over a ilat portion 73 of the enlarged diameter portion 24 of the shaft 4 25. The drive lug 71 is engaged by the fiat portion 73 of the shaft 25 upon rotation of said shaft in a direction, which is shown in FIG. 3 as a counterclockwise direction, to rotatably drive the cam 26 from the shaft 25, but to accommodate limited free movement of said timer cam' Iwith respect to the shaft, to accommodate resetting of said timer cam at the termination of a timing operation, by the resetting lever 17.

The shaft 25, extending outwardly of the timer cam 26 toward the side wall 12, is commonly termed a D shaft and has oppositely disposed flat portions 75 of said shaft forming a mounting and positive drive for the timer cam 27. The timer cam 27 has a low portion 76 forming a circumferential extension of the high portion 58 of said timer cam and accommodating the follower end portion 56 of the switch arm 49 to drop from the high portion of said cam to engage the contact 53 with the contact bar 30, to effect the completion of a circuit from the conductor 33 and contact bar 30` to the conductor 44, to energize an energizing circuit, such as the solenoid of a water ll Valve, and effect opening of the valve for a predetermined time interval.

The timer cam 27 is abutted by a time interval modifying cam 77, mounted on the shaft 25 for relative move- `ment with respect thereto. The modifying cam 77 has a raised cam surface 78 of the same height as the cam surface 58, and has a radially inwardly spaced portion 79 of the same diameter as the surface 76 of the cam 27. As shown in FIG. 2 the modifying cam has a hub portion 77a abutting a furcation 80 of a bifurcated support 180a, for the reset lever 17, and has a knob portion 81 extending through said furcation and the bearing support formed between the wall 12 and the mating right angled portion of the cover 15. A washer y82, which may be made from a plastic material having antifriction qualities, is interposed between the furcation 80 and the inside of the wall 12 to take up between said furcation and wall.

A clutching connection is provided between the cam 27 and the modifying cam 77, which is herein shown as being in the form of a radial serrations or teeth 83 formed in the end face of the cam 27 and engaging similar radial serrations or teeth formed in the adjacent end face of the modifying ca-m 77. The spring 63 maintains said teeth in engagement with each other to effect a drive from the cam 27 to the cam 77 and to accommodate relative movement of the cam 77 with respect to the cam 27 to vary the length of the raised cam face 58. 'Ihe interval of on time of the switch 49 may thus be selected by lengthening or shortening the cam face 58.

Relative movement of the cam 77 with respect to the cam 27 is limited by diametrically spaced pins or lugs 85 extending vfrom the cam 77 into circumferential slots 86 formed in the cam 27 (FIG. 2).

By way of example and not limitation, forty-four radial serrations or teeth 83 are provided on the side of the cam 27 facing similar radial teeth on the facing side of the modifying cam 77. The cam 27 for example may be driven by the timer motor 20 to rotate 4at the rate of one revolution each 44 seconds. Thus as the modifying cam 77 is adjusted in a clockwise or counter-clockwise direction to either shorten or lengthen the cam surface 5'8, each tooth or click, as the modifying cam 77 is moved relative to the cam 27, will represent a time interval of 1 second.

In FIG. 7 the raised camming surface 718 of the modifying cam 77 is shown in phantom, in an extreme position of adjustment in a counterclockwise direction with the lugs 8S in the extreme ends of the slots 86 in a counterclockwise direction. This will hold the switch 49 open for a maximum time and give a minimum on time of the switch 49. As the modifying cam is turned in a clockwise direction by its knob !81, as shown in FIGS.` 3 and 5, the raised camming surface 58 of the cam 27 will Ibe shortened, with a resultant increase of on time of the switch 49, and an increased delivery of water, where the timer switch 49 may control the energization of a water fill valve solenoid, for lling the ice mold trays of an ice maker.

Referring now in particular to the resetting mechanism', operated by the reset lever 17, said reset lever is shown in FIGS. 2 and 3 as mounted on the bifurcated bracket 80a. the furcations 80 of which are mounted for pivotal movement coaxial with the axis of the cam shaft 25, adjacent opposite ends of said cam shaft.

'Ihe reset lever 17 is of a generally trough-like form in end view and has side walls 90 and 91 diverging from its free end and riveted or otherwise secured to angularly disposed base portions 92 and 93 of the bracket 80a. Drainage holes 17a are provided in the bottom of said reset lever, to accommodate the drainage of water, where the timer may be used in an ice maker. The angularly disposed base portions `92 and 93 of the bifurcated bracket `80a and the diverging wall portions 90 and 91 of the reset lever 17 are disposed in such angular relation with respect to each other as to prevent entrance of the fingers through said opening into the casing 10.

The base portion 93 of the rockable bracket 80a is shown in FIG. 3 as having a pawl or ratcheting dog 95 riveted thereto adjacent the outer end thereof, as by a rivet 96. The ratcheting dog 95 is engageable with a one tooth ratchet in the form of an abutment end portion 97 of a rib 99, extending about the inner side of the timer cam 26 and terminating into the raised portion 57 of said timer cam. Said raised portion 57 extends across said cam for the width thereof. It will be noted from FIG. 3 that the raised portion of the cam is relatively short in a circumferential direction and just long enough to lift the switch arm to disengage the contact 51 from the contact bar 30 at the termination of a timing operation.

A tension spring 100 is shown as being hooked at one end to the upper end of the base portion 93 of the bracket 89 and at its opposite end to the end wall 13, adjacent the upper end thereof, to bias the ratchet dog 95 out of engagement with the abutment end 97 of the rib 99.

Thus when the contacts of the switch arm 46 are open and the end of said switch arm is riding on the raised portion 57 of the cam 26, and it is desired to reset the timer and initiate operation of the timer motor, it is only necessary to pivot the reset lever 17 in a counterclockwise direction, to engage the end of the pawl or ratcheting dog 9'5 with the abutment end 97 of the rib 99 and move the cam 26 in a counterclockwise direction, to accommodate the switch arm to drop off the raised portion of the cam and engage the contact 51 thereof with the contact bar 30 to energize the timer motor 19, and thereby start a timing cycle.

As the follower end portion 55 of the switch arm 46 rides olf the raised camming surface 57 of the cam 26 the contact 51 will engage the contact bar 30 and energize the timer motor 19. This will eifect a drive to the timer shaft 25 in a countercloc-kwise direction and bring the flat portion 73 of the timer shaft 25 into engagement with the drive pin 71 and rotate the timer motor cam 26, the. cam 27 and the modulator cam 77 in a clockwise direction.

It should here be noted that the dog 95 can only engage the abutment end portion 97 of the rib 99 to reset the switch 46 When the cam 26 has rotated a full cycle of rotation and the motor 19 is deenergized. Once the timer motor has been energized, the abutment end portion is out of range of the ratcheting dog 95 `and stays out of range of said dog until completion of the timing cycle. The dog `95 thus is ineffective to change the setting of the timer cam 26 until the switch I46 has again been moved out of engagement with the contact bar 30 by the raised portion 57 of the timer cam, to deenergize the timer motor. Thus repeated actuation of the lever 17, after the contact 51 of the switch 46 is in contact with the contact bar 30, will have no affect on the timer motor cam 26, and the reset lever 17 may be moved back and forth during the entire cycle of operation of the timer without 6 affecting operation of the timer motor cam 2'6 and the timing cycle of the timer cam 27 and modulator cam 77.

Suitable indicia may be placed on the knob 81 and an indicia plate 81a abutting the timer casing on the side thereof adjacent the knob 81, to indicate the on time of the switch 49. The timer 10 thus serves to time the on time of an energizing circuit and to enable the period of the on time to be accurately selected.

OTH-ER EMBODIMENTS In FIGS. 6, 7, 8 and 9, we have shown modified forms in which the invention may be embodied. In the embodiments of the invention shown in these figures, the motor, timer casing and switch structures are similar to those shown in FIGS. l to 5, so like reference numerals will be applied to like parts shown in FIGS. l through 5 and the description thereof need not herein be repeated.

In FIG. 6 a cam body 101 has a timer motor control cam 102 and a circuit energizing cam 1013 formed integrally therewith. The cams 102 and 103 cooperate with follower end portions 104 and 105 respectively of resilient switch arms 106 and 107 in the same manner as in the form of the invention illustrated in FIGS. l to 5. The cam body has an integral shaft portion 109 extending through a hub 110 and knob 111 of the modulator cam, and extending in an opposite direction through the inner end of a clutching member 113, into engagement with the end of a shaft for the pinion 22. The pinion 22 is splined to the clutching member 113. A spring 116 encircling the shafts 115 and 109 biases the clutching member 113, to engage radial teeth 117 on its inner face with corresponding radial teeth (not shown) on the end face of the cam body 101.

The end face of the cam body 101 opposite the clutching member 113 has radial serrations or teeth 119 engageable with corresponding teeth (not shown) formed in the adjacent face of a modulator cam 112. The radial teeth 119 are biased into engagement with the teeth of the modulator cam 112, as by a compression spring 121 encircling the hub 110. The modulator cam 112 may thus be adjusted by pulling outwardly on the knob 111 against the spring 121 and turning said modulator cam relative to the circuit energizing cam 103, to vary the on time of the switch arm 107. At the termination of the timing operation, the timer may be reset by an actuating lever 123 formed integrally with the cam body 101 and extending radially therefrom, through a slot 125 formed in the bottom wall of the switch casing. An open portion 126 is formed in a switch 126a between contact bars 127, 128, engaged by the respective switch arms 106 and 107, to accommodate rotation of the actuating lever 123 for substantially a complete cycle of rotation of the cam body from an on position of the switch 106 to its off position, as it rides up onto a raised portion 129 of the cam 102.

In FIG. 7 a timer motor cam 130 and a circuit energizing cam 131 are integrally formed on a cam body 132 driven from a drive pinion 22 through a spring biased clutch 133 like the clutch 113, so not herein shown or described further.

The cam body 132 is mounted on a flattened or D portion 135 of a shaft 136, and is retained from movement in a direction to release the clutch by a washer 137, which may be a C washer. A compression spring 139, which serves to engage the clutch 133, biases the clutch body 132 into engagement with the washer 139. The cam body 132 has diametrically spaced stop lugs 140` extending axially thereof into circumferential slots 141 formed in a modulator cam 142. The modulator cam 142 is biased into engagement with the shoulder 143 formed by the juncture of the ilatted portion of the shaft 136 with the round portion thereof, by the spring 139. A clutch in the form of radial serrations or teeth 144 is provided between the cam body 132 and the modulator cam 142, to drive said modulator cam with the cam 131.

The modulator cam 142 is adjustably moved relative a circuit to be energized, by a knob 145 extending outwardly of the timer casing. The knob 145 is shown as being hollow and as extending along the cam shaft 136 and forming a mounting for the free end portion of said cam shaft. A compression spring 147 seated on the end of the shaft 136 and the closed end of the hollow portion of the knob 145 is provided to bias the knob 145 toward the side wall of the timer casing. The knob 145 has an enlarged diameter portion or hub 148 formed integrally therewith within the timer casing and having a drive slot 149 formed therein engaged by a lug 150 extending axially of the modulator cam 142.

When it is desired to change the adjustment of the modulator cam, the knob 145 is depressed to engage the drive lugs 140 and move the cam body 132 against the spring 139 to release the teeth 144. The modulator cam 142 may then be turned by the drive connection between the slot 149 and lug 150, to modulate the raised surface d of the cam 131, within the limits of the slots 141 formed in said modulator cam. A reset lever 151, like the reset lever 117, is mounted for adjustable movement about the axis of the shaft 136 and has a ratcheting dog or pawl (not shown) thereon, engageable with an end face 153 projecting radially of the cam body 132, to move said cam body in a direction to release a switch arm 155, controlling energization of the timer motor, from the raised portion of the timer motor cam 130.

In FIG. 8 we have shown a cam body 155, similar to the cam body 101 shown in FIG. 2, and have shown a drive clutch 156` for rotatably driving said cam body from a pinion 157 splined to an internal coupling part 159 of said spring clutch. In this form of the invention there is no modulator cam to enable the on time of the energizing circuit to be selected. The timer is reset by a reset lever 158 mounted within the clutch casing coaxial of the axis of rotation of the cam body 155 and having a ratcheting dog (not shown) thereon having engagement with a ratchet tooth in the form of an end face 161 extending radially of the cam body 155, to move a raised portion 163 of the timer motor cam to release a switch arm 165 and close an energizing circuit to the timer motor.

In the modification of the invention illustrated in FIG. 9, a timer cam 170, like the timer earn 26 shown in FIG. 2, is mounted on a timer shaft 171 in the same manner the timer cam 26 is mounted on the timer shaft 25, and is driven by said timer shaft upon engagement of a fla-t portion 172 of said shaft with a drive lug 173 extending axially of the body of the timer cam, in radially spaced relation with respect to the axis of rotation of the timer shaft.

A modulator cam 175 is mounted on the timer shaft 171 for free rotation with respect thereto and serves to modify the camming surface of a timer cam 176. The

timer cam 176 is mounted on a flattened or D portiony 179 of the timer shaft 171 to be positively driven by said shaft. A retaining ring 180, which may be a snap ring, retains the timer cam 177 from movement along the timer shaft 171 in a direction away from the modulator cam 175. A compression spring 181 encircling the timer shaft 171 is interposed between the timer cam 176 and the modulator cam 175, to bias the modulator cam 175 into engagement with the cam 176, to be rotatably driven therefrom. A radially serrated drive connection may be provided between the cams 175 and 176. An adjustment knob 183 is mounted on the free end portion of the timer shaft 171 and forms a support therefor. A compression spring 184 interposed between the end of the timer shaft 171 and the outer end portion of the knob 183 biases the knob 183 outwardly with respect to the timer casing. Formed integrally with the adjustment knob 183 and disposed inside of the timer casing is an enlarged diameter body portion 185, having diametrically spaced drive pins 186 and 187 free from the timer cam 176, within predetermined limits, and extending within outwardly opening slotted portions 188 and 189 respectively of the modulator cam 175. The lugs 186 and 187 are relatively movable with respect to the timer cam 176 and engage the ends of the slotted portions 188 and 189, to adjust the modulator cam with respect to the timer cam 176 upon depression of the knob 183 to disengage the clutching connection between the cam 176 and the modulator cam 175.

A reset lever 193 like the reset lever 17 is mounted coaxially of the shaft 171 for relative movement with respect to said shaft. The reset lever 193 has a racheting dog (not shown) extending therefrom toward the cam 176, to engage a ratchet tooth in the form of an engaging end portion 195 of a rib 196 extending partially about the cam 170, to pivot said cam relative to the timer shaft 171, at the termination of a timing operation, and reset the timer motor in the same manner the reset cam 17 serves to reset the cam 26.

While we have herein shown and described several forms in which the invention may be embodied, it should be understood that various variations and modifications in the invention may be attained without departing from the spirit and scope of the novel concepts thereof.

We claim as our invention:

1. An interval timer for timing the interval of energization of a circuit comprising:

(a) a timer motor,

(b) first switch means controlling energization of said timer motor,

(c) second switch means effecting energization of said circuit for a preselected time interval,

(d) a rotatable first cam having a camming surface effecting the opening of said first switch means and the deenergization of said timer motor,

(e) a second rotatable cam, rotatable about the axis of said first rotatable cam and having a camming surface for effecting the opening of said second switch means and the deenergization of said circuit,

(f) a drive connection from said timer motor to both of said cams,

(g) and a resetting lever for said first cam moving said camming surface thereon away from said switch means and initiating the energization of said timer motor, said lever being disposed adjacent the periphery of said first cam and said first cam having an abutment thereon in radially spaced relation with respect to the axis of rotation of said first cam in position to be engaged by said lever only when said first switch means is on said camming surface, and operable upon movement of said lever to move said first switch means off of said camming surface and effect closing of a circuit through said switch means.

2. A timer according to claim 1, wherein the abutment on said first cam is in the form of a single ratchet tooth,

wherein a ratcheting dog is operated by said resetting lever and is engageable with said ratchet tooth, and

wherein spring means biases said ratcheting dog out of engagegment with said ratchet tooth.

3. A timer according to claim 1, wherein said drive connection includes:

(a) a shaft coaxial with said first and second cams,

(b)haf drive connection from said timer motor to said s a t,

(c) a lost motion drive connection from said shaft to said first cam, and

(d) a direct drive connection from said shaft to said second cam.

4. A timer according to claim 1, wherein a modifying cam is provided to adjust the length of the camming surface of said second cam and the interval of energization of the circuit, independently of operation of said reset lever.

5. A timer according to claim 3, wherein the means for adjusting the camming surface of said second cam includes:

(a) a modifying cam is mounted on said shaft for relative rotation with respect to said shaft, and

10 (in) a resetting lever mounted for free pivotal movement about an axis coaxial with the axis of rotation of said shaft and cams and biased into a position free from said first cam, and (n) a ratcheting dog on said resetting lever engageable (b) a clutching connection between said second cam with said first cam upon manual movement of said and said modifying cam, accommodating relative resetting lever against its bias, to pivot said first cam movement of said modifying cam with respect to said relative to said shaft and effect full closing of said second cam, to vary the length of the camming surfirst switch to initiate operation of said timer motor. face of said second cam, without affecting the cycle 10. The structure of claim 9, of operation of said motor. (a) wherein the resetting lever extends through said 6. A timer according to claim 5, opening and has bifurcated end portions mounted for (a) wherein the resetting lever is mounted coaxially of free rotation relative to said shaft and cams and said shaft and has a ratcheting dog extending therehas skirt portions connected with said bifurcated porfrom for engagement with the abutment surface 0n 15 tions and extending therefrom through said opening said first cam to move said first cam relative to said and terminating at their Outer end portionS into a shaft and reset the timer motor after a complete timtrough-'like leVer, and ing cycle independently of variations in time intervals (b) Wherein Said Skirt PortOnS Serve as a Safety guard of energization of the energizing circuit, and for said opening to prevent the fingers from entering (b) wherein yieldable means bias said ratcheting dog said npeningiii all Positions 0f seid leVer With resPeCt out of engagement with said abutment surface on said t0 Said Openingiirst cam. 11. A timer according to claim 9,

7 A timer according to clairn 51 wherein the clutching (a) wherein the energizing circuit is effective to initiate connection comprises interengaging radial toothed serraan iCe tray illliiig Operation, tions on the adjacent faces of said second cam and said (h) Wheiein Said lever iS apertured at its bottom to aC- modifying cam, and spring means biasing said toothed Commodate the dralnage of water therethrough, and Serrations into engagement with each other (c) wherein a spring is connected with said lever and 8, A tirner according to clairn 7, including; a knob biases said lever into a position free from said first having operative connection with said modifying cam for Cami. moving said modifying cam relative to said second cam 12- A timer eCCOrdliigvtO Claim 10, to vary the length of the camming face thereof and the (a) Whereiri the Cliitehiiig Connection between the timer resultant time interval of energizationof the energizing C erii and the in OdifYing Cam COmPriSeS radial Serracircuit without affecting the cycle of operation of said tiOiiS 0n the adJaCent faCeS 0f Said CamS, and timer nioton (b) wherein spring means bias said radial serrations 9, An interval timer comprising; into engagement with each other to effect a drive (a) a casing having from said second cam to said adjustment cam.

(l) opposite side and end walls, and 13 The Structure 0f Claim 12, (2) at least one other wall connecting said side and (a) Whereiii riieaiis are Provided t0 liiiiit adjustable .end Walls together and movement of said modifying cam with respect to said (a) an opening in said other wall extending second C am, and

between said Side Walls, (b) wherein a `knob is provided on the outside of said (b) a timer motor mounted on one side wall, Casilla for adjustabiy movinasaid modifying Cam (c) a shaft rotatably mounted Within Said casing berelative to sa1d second cam against the clutching contween Said Side Walls, nection independently of operation of said resetting (d) a drive connection from said motor to said shaft, ieYer, t0 Vary the On Period 0f the energizing Cir- (e) a rst switch controlling energization of said timer C uit Without affecting the Cycle 0f Operation of Said motor, timer motor.

(f) a second switch effecting energization of a circuit, 14- The structure 0f Claim 13] Wherein the Cllltehrlg (g) a first cam mounted on said shaft for relative rota- Connection is released by depressing said knOh.

tion with respect thereto,

(h) a lost motion drive connection between said shaft References Cited and said rst cam, UNITED STATES PATENTS (i) said first cam having a camming surface thereon 2,343,951 3/1944 Blodgett 318-484 operating said first switch to energize said timer 2,656,424 10/ 1953 Frerer 200-27X motor, 2,662,943 12/1'953 Morrison ZOO-31X (j) a second cam mounted on said shaft for rotation 2,776,384 1/ 1957 Long i 20G-22X therewith and having a camming surface thereon en- 2,832,854 4/ 1958 Doyle 20G-25X gaged by said second switch for effecting opening 3,160,719 12/ 1964 Seidel 20D- 31X of said switch,

(ik) a modifying cam adjustable relative to said second cam to vary the length of said camming surface and the interval of closing of the second switch,

(l) a clutching connection between said modifying cam and said second cam,

ORIS L. RADER, lPrimary Examiner A. G. COLLINS, Assistant Examiner U.S. Cl. XJR.

ZOO- 22; 307-141 

